The Seasonal Variation Of Diarrhetic Shellfish Poisoning In Lingshan Bay And Haizhou Bay

Shellfish toxins produced by harmful algae cause a global problem for food safety and aquaculture industry. In recent years, shellfish is always reported contaminated by diarrhetic shellfish poisoning toxins(DSP), from the northern Yellowsea to the South China sea, sometimes critically above the government level, then much more attention should be payed. Solid phase adsorption toxin tracking(SPATT) is a new monitoring tool that simulates the toxin contamination of filter feeding bivalves using passive samplers containing adsorption substrates. Coupled with appropriate analytical technologies such as LC-MS/MS and ELISA assays, the method is both easy done and highly sensitive. SPATT has several important advantages over current phytoplankton and shellfish monitoring methods, thus the studies have been carried out in various parts of the world.The study here is the first application of SPATT for a long-term monitoring of various of DSP toxins in waters of Lingshan Bay and Haizhou Bay, the Yellow sea. From the study, the followings are known. First, toxins of Okadaic acid(OA), Dinophysistoxin-1(DTX-1), Pecenotoxin(PTX-2) exist in both bays, traces of YTX were detected in Lingshan Bay only in summer months, and Dinophysistoxin-2(DTX-2) did not exist. Secondly, same information is known in the shellfish farming ponds near Haizhou Bay, traces of OA and PTX-2 were found in the ponds, with a highest value of 2.24ng/g of total DSP, and this is useful for the cleaning of toxins contaminated shellfish.Thirdly, DSP is of high content in spring, summer and autumn months, with severe variations, low in winter months, which is true in both bays.